1. Field of the Invention
This invention relates to transdermal drug delivery systems. In another aspect this invention relates to transdermal drug delivery systems containing melatonin.
2. Description of the Related Art
Transdermal drug delivery systems are designed to deliver a therapeutically effective amount of drug across the skin of a patient. Devices known to the art include reservoir type devices involving membranes that control the rate of drug release to the skin and devices involving a dispersion of the drug in a matrix such as a pressure sensitive adhesive. As the skin presents a barrier to the drug it is often desirable or necessary to incorporate certain materials that enhance the rate at which the drug passes through the skin. For any particular drug, however, the type of devices, the transdermal flux rate that is suitable, and the suitable formulation components are dependent upon the particular drug to be delivered.
Melatonin, N-[2-(5-methoxy-1H-indol-3-yl)ethyl]acetamide, is a hormone synthesized and secreted by the pineal gland. Melatonin shows a circadian variation with high nocturnal but low or undetectable diurnal plasma concentrations. Melatonin has been studied for a variety of therapeutic applications.
U.S. Pat. No. 4,600,723 (Short et al.) discloses the use of melatonin to alleviate or prevent the negative effects associated with disturbances in circadian rhythms of bodily performance and function which may occur for example in transfer of work patterns from day to night shift or rapid crossing of several times zones (jet lag).
U.S. Pat. No. 4,654,361 (Samples et al.) discloses the use of melatonin to lower intraocular pressure in a human having abnormally high intraocular pressure.
U.S. Pat. No. 4,945,103 (Cohen) discloses the use of melatonin to treat premenstrual syndrome.
European Patent Application 0 438 856 A2 (Fukuda et al.) discloses the use of melatonin to protect the skin against the influence of ultraviolet radiation.
European Patent Application 0 518 468 A1 (Zisapel) discloses the use of melatonin to prevent sudden infant death syndrome.
Decreased plasma melatonin levels in migraine patients have been reported in Headache 1989, 29, 241 (Claustrat et al.).
U.S. Pat. No. 4,411,893 (Johnson et al.) discloses the use of certain amine oxides to enhance the penetration of therapeutic agents into and through skin.